The invention relates to a dispenser for various flowable media, which can be in gaseous, liquid, pasty, or pulverulent form.
According to the invention, the dispenser has a pressure chamber connected by an outlet channel to a dispensing opening, such as a nozzle, and/or at least one valve, which can be an inlet valve, an outlet valve or some other valve, so that operation can be reliably controlled.
A further problem of the invention is to avoid the disadvantages of known constructions and, in particular, to obtain a high positional security or a very reliable closure by the particular valve.
This problem is solved in that at least one valve is fixed in at least one position, particularly in the closed position, by at least one restraint in the manner of a snap-action holding and release mechanism or the like, so that in the case of an open position it is immovable or in the case of a closed position the valve can be held in such a way that the restraint can only be overcome by applying a predetermined disengaging force and then it occurs suddenly, so as to pass into from one operating state to another operating state.
Appropriately a catch is formed to operate directly by the contact between a valve body and a valve seat. For the accurate, simple determination of the locking force, the valve body is axially or symmetrically constructed. The valve body can be inserted as a closed standard component in a jacket having a channel portion. The jacket forms a valve seat along the channel portion.
The restraint or catch can also be produced by a fluid, against which the valve operates when transferred between two positions under pressure changes. This leads to a type of fluid suspension or damping. For example, the valve body can restrict or block a pressure chamber that is pressurized by a gas or air introduced into a bore portion connected to the valve seat. By changing the conditions between two portions of the pressure chamber associated with the two valve positions, it is possible to adjust the restraining force.
The fluid pressure can also act as a restoring spring for restoring the valve to at least one position, particularly the closed position.
Particularly when the dispenser is constructed as a one-way and/or disposable dispenser, so that the total stored medium volume is substantially completely discharged following a complete pump stroke, the valve as an outlet valve can also merely form a hermetically tight closure of the medium or pump chamber in the vicinity of the outlet channel. Under the pumping pressure, this closure is transferred into its open position, where it is secured by a jamming, locking or stop engagement. The valve construction is particularly suitable for dispensers in accordance with German Patent Application DE-OS 35 32 890, to which reference should be made for further details and effects.
Particularly if the dispenser is constructed according to the inventor's German Patent Application P 39 09 031.0, assigned to the assignee of the present invention, to which reference should be made, it can be advantageous to form a displacement or valve body mechanically connected to a pump cylinder by a separate component, which is made from a different material than the cylinder and is connected thereto, e.g. by means of a fixed connecting member. Therefore, the cylinder can then be constructed in a simple manner as a container made from glass or a material having similar characteristics. A material such as glass would be too inelastic for use as the valve or displacement body. The more elastic displacement body forms, together with the hard glass container, a closed standard component.
These and other features of the invention will be apparent from the disclosure provided by the claims, the description and the drawings, which follow. In the description, reference is made to the accompanying drawings, which form a part hereof, and which illustrate examples of the invention. Such examples, however, are not exhaustive of the various embodiments of the invention and, therefore, reference is made to the claims which follow the description for determining the scope of the invention.